An evaluation of the role of Src in renal cancer.
358 Background: The aim of the current study was to assess the expression levels of c-Src, phosphorylated Src, dephosphorylated c-Src at 530 and the downstream marker Fak 861 in renal cancer. Methods: In all, 60 patients undergoing potentially curative nephrectomy for localised renal cancer were included. Imunohistochemical staining was utilised to assess expression of c-Src, dephosphorlated c-Src at 530, phosphorylated Src at the Y416 site, and Fak 861. Expression was assessed using the weighted histoscore method. Results: High membrane c-Src was associated with increased cancer specific survival (p=0.032). In addition, increased cancer-specific survival was associated with high levels of cytoplasm and membrane expression of c-Src (p=0.039). When assessed individually, membrane, cytoplasm and nuclear expression of phosphorylated Src was not significantly associated with cancer specific survival. However when membrane and cytoplasm expression was combined, high expression was associated with decreased cancer specific survival (p=0.001). Low cytoplasm Fak expression was associated with increased cancer specific survival (p=0.029). When expression of Fak was combined with phosphorylated Src, high expression was associated with decreased cancer specific survival (p=0.003). When taking together high membrane c-Src and phosphorylated Src expression, this was associated with increased cancer specific survival (p=0.029). On multivariate analysis, combined expression of membrane c-Src and phosphorylated Src (HR 0.49, 95% CI 0.24-0.99, p=0.047) and combined Fak and phosphorylated Src expression (HR 1.88, 95% CI 1.06-3.34, p=0.030) were significant independent predictors of cancer specific survival. Conclusions: The results suggest that activated c-Src is associated with improved survival and activated Src family members are associated with decreased survival. This would suggest that another member of the Src family maybe associated with decreased survival. Further work is required to identify which of the Src family members are expressed in renal cancer and would therefore allow specific inhibitors for these Src family members to be developed. No significant financial relationships to disclose.